Commiting RIP. RIP should somehow listen, will not reply. I needed to

commit it so that whole thing compiles.

Makefile

@@ -9,7 +9,7 @@ OPT=-O2
 DEBUG=-g#gdb
 CFLAGS=$(OPT) $(DEBUG) -Wall -W -Wstrict-prototypes -Wno-unused -Wno-parentheses
 
-PROTOCOLS=
+PROTOCOLS=rip
 LIBDIRS=sysdep/linux sysdep/unix lib
 STDDIRS=nest $(addprefix proto/,$(PROTOCOLS))
 DIRS=$(STDDIRS) $(OBJDIR)/lib

proto/rip/Makefile

@@ -0,0 +1,4 @@
+THISDIR=proto/rip
+OBJS=rip.o
+
+include ../../Rules

proto/rip/rip.c

@@ -0,0 +1,311 @@
+/*
+ *	Rest in pieces - RIP protocol
+ *
+ *	(c) 1998 Pavel Machek <pavel@ucw.cz>
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#define LOCAL_DEBUG
+
+#include <string.h>
+#include <stdlib.h>
+
+#include "nest/bird.h"
+#include "nest/iface.h"
+#include "nest/protocol.h"
+#include "nest/route.h"
+#include "lib/socket.h"
+#include "lib/resource.h"
+#include "lib/lists.h"
+#include "lib/timer.h"
+
+#include "rip.h"
+
+int infinity = 16;
+
+/* XXX should be 520 */
+#define RIP_PORT 1520
+
+static void
+rip_if_notify(struct proto *p, unsigned c, struct iface *old, struct iface *new)
+{
+}
+
+static void
+rip_reply(struct proto *p)
+{
+  P->listen->tbuf = "ACK!";
+  sk_send_to( P->listen, 5, P->listen->faddr, P->listen->fport );
+}
+
+#define BAD( x ) { log( L_WARN "RIP/%s: " x "\n", p->name ); return; }
+
+static int
+process_authentication( struct proto *p, struct rip_block *block )
+{
+  return 0;
+}
+
+static struct rip_entry *
+find_entry( struct proto *p, ip_addr network, ip_addr netmask )
+{
+  struct node *e;
+
+  CHK_MAGIC;
+  WALK_LIST( e, P->rtable ) {
+    if (ipa_equal( network, E->network ) &&
+	ipa_equal( netmask, E->netmask )) {
+      return E;
+    }
+  }
+  return NULL;
+}
+
+#define ipa_from_u32(a) (*(ip_addr *) &a)
+
+static struct rip_entry *
+new_entry( struct proto *p, struct rip_block *b, ip_addr whotoldme )
+{
+  struct rip_entry *e;
+
+  e = mb_alloc(p->pool, sizeof( struct rip_entry ));
+  e->whotoldme = whotoldme;
+  e->network = ipa_from_u32( b->network );
+  e->netmask = ipa_from_u32( b->netmask );
+  /* FIXME: verify that it is really netmask */
+  if (b->nexthop)
+    e->nexthop = ipa_from_u32( b->nexthop );
+  else
+    e->nexthop = whotoldme;
+  e->tag = ntohs( b->tag );
+  e->metric = ntohl( b->metric );
+  e->updated = e->changed = now;
+  
+  return e;
+}
+
+static void
+kill_entry( struct proto *p, struct rip_entry *e )
+{
+  struct rip_connection *c;
+
+  rem_node( NODE e );
+  WALK_LIST( c, P->connections ) {
+    if (c->sendptr == e)
+      die( "kill_entry: one of connections has this as current, fix me!" );
+  }
+  mb_free( e );
+}
+
+#define DELETE( msg ) { debug( msg ); kill_entry( p, e ); e = NULL; }
+
+static void
+process_block( struct proto *p, struct rip_block *block, ip_addr whotoldme )
+{
+  struct rip_entry *e;
+  int metric = ntohl( block->metric );
+  ip_addr network = ipa_from_u32( block->network );
+
+  CHK_MAGIC;
+  if ((!metric) || (metric > infinity)) {
+    log( L_WARN "Got metric %d from %I\n", metric, whotoldme );
+    return;
+  }
+
+  /* XXX Check if destination looks valid - ie not net 0 or 127 */
+
+  /* XXX Should add configurable ammount */
+  if (metric < infinity)
+    metric++;
+
+  debug( "block: %I tells me: %I available, metric %d... ", whotoldme, network, metric );
+
+  e = find_entry( p, network, ipa_from_u32( block->netmask ) );
+  if (e && (e->metric > metric)) /* || if same metrics and this is much newer */ 
+    DELETE( "better metrics... " );
+
+  if (e && ((e->updated - now) > 180))
+    DELETE( "more than 180 seconds old... " );
+
+  if (e && ipa_equal( whotoldme, e->whotoldme ) &&
+      (e->metric == metric)) {
+    debug( "old news, updating time" );
+    e->updated = now;
+  }
+
+  if (!e) {
+    debug( "this is new" );
+    e = new_entry( p, block, whotoldme );
+    add_head( &P->rtable, NODE e );
+  }
+
+  debug( "\n" );
+}
+#undef DELETE
+
+static void
+rip_process_packet( struct proto *p, struct rip_packet *packet, int num, ip_addr whotoldme, int port )
+{
+  int i;
+
+  switch( packet->heading.version ) {
+  case RIP_V1: debug( "Warning: I do not talk ripv1\n" ); break;
+  case RIP_V2: break;
+  case '!': debug( "OOk, sir!\n" ); break;
+  default: BAD( "Unknown version" );
+  }
+
+  switch( packet->heading.command ) {
+  case 1: debug( "Asked to send my routing table\n" ); break;
+  case 2: debug( "Part of routing table came\n" ); 
+          if (port != RIP_PORT) {
+	    log( L_AUTH "%I send me routing info from port %d\n", whotoldme, port );
+	    return;
+	  }
+
+	  if (!neigh_find( p, &whotoldme, 0 )) {
+	    log( L_AUTH "%I send me routing info but he is not my neighbour\n", whotoldme );
+	    return;
+	  }
+
+	  /* Should check if it is not my own packet */
+
+          for (i=0; i<num; i++) {
+	    struct rip_block *block = &packet->block[i];
+	    if (block->family == 0xffff)
+	      if (!i) {
+		if (process_authentication(p, block))
+		  BAD( "Authentication failed\n" );
+	      } else BAD( "Authentication is not the first!" );
+	    process_block( p, block, whotoldme );
+	  }
+          break;
+  case 3:
+  case 4: BAD( "I was asked for traceon/traceoff\n" );
+  case 5: BAD( "Some Sun extension around here\n" );
+  case '!': debug( "He gave me!\n" ); break;
+  default: BAD( "Unknown command" );
+  }
+
+  rip_reply(p);
+}
+
+static void
+rip_rx(sock *s, int size)
+{
+  struct proto *p = s->data;
+  int num;
+
+  CHK_MAGIC;
+  debug( "RIP: message came: %d bytes\n", size );
+  if (size <= 0) BAD( "Zero sized packet" );
+  size -= sizeof( struct rip_packet_heading );
+  if (size < 0) BAD( "Too small packet" );
+  if (size % sizeof( struct rip_block )) BAD( "Odd sized packet" );
+  num = size / sizeof( struct rip_block );
+  if (num>25) BAD( "Too many blocks" );
+
+  rip_process_packet( p, (struct rip_packet *) s->rbuf, num, s->faddr, s->fport );
+}
+
+static void
+rip_dump_entry( struct rip_entry *e )
+{
+  debug( "%I told me %d/%d ago: to %I/%I go via %I, metric %d\n", 
+  e->whotoldme, e->updated-now, e->changed-now, e->network, e->netmask, e->nexthop, e->metric );
+}
+
+static void
+rip_timer(timer *t)
+{
+  struct proto *p = t->data;
+  struct rip_entry *e, *et;
+
+  CHK_MAGIC;
+  debug( "RIP: tick tock\n" );
+
+  WALK_LIST_DELSAFE( e, et, P->rtable ) {
+    if ((now - E->updated) > (180+120)) {
+      debug( "RIP: entry is too old: " );
+      rip_dump_entry( E );
+      kill_entry( p, E );
+    }
+  }
+}
+
+static void
+rip_start(struct proto *p)
+{
+  debug( "RIP: initializing instance...\n" );
+
+  P->listen = sk_new( p->pool );
+  P->listen->type = SK_UDP;
+  P->listen->sport = RIP_PORT;
+  P->listen->rx_hook = rip_rx;
+  P->listen->data = p;
+  P->listen->rbsize = 10240;
+  P->magic = RIP_MAGIC;
+  if (sk_open(P->listen)<0)
+    die( "RIP/%s: could not listen\n", p->name );
+  init_list( &P->rtable );
+  init_list( &P->connections );
+  P->timer = tm_new( p->pool );
+  P->timer->data = p;
+  P->timer->randomize = 5;
+  P->timer->recurrent = 30; 
+  P->timer->hook = rip_timer;
+  tm_start( P->timer, 30 );
+
+  debug( "RIP: ...done\n");
+}
+
+static void
+rip_init(struct protocol *p)
+{
+  debug( "RIP: initializing RIP...\n" );
+}
+
+static void
+rip_dump(struct proto *p)
+{
+  int i;
+  node *w, *e;
+  i = 0;
+  WALK_LIST( w, P->connections ) {
+    struct rip_connection *n = w;
+    debug( "RIP: connection #%d: %I\n", i, n->addr );
+  }
+  i = 0;
+  WALK_LIST( e, P->rtable ) {
+    debug( "RIP: entry #%d: ", i++ );
+    rip_dump_entry( E );
+  }
+}
+
+static void
+rip_preconfig(struct protocol *x)
+{
+  struct proto *p = proto_new(&proto_rip, sizeof(struct rip_data));
+
+  debug( "RIP: preconfig\n" );
+  p->preference = DEF_PREF_DIRECT;
+  p->start = rip_start;
+  p->if_notify = rip_if_notify;
+  p->dump = rip_dump;
+}
+
+static void
+rip_postconfig(struct protocol *p)
+{
+}
+
+struct protocol proto_rip = {
+  { NULL, NULL },
+  "RIP",
+  0,
+  rip_init,
+  rip_preconfig,
+  rip_postconfig
+};
+

proto/rip/rip.h

@@ -0,0 +1,60 @@
+/*
+ * Structures for RIP protocol
+ */
+
+struct rip_connection {
+  ip_addr addr;
+  struct rip_entry *sendptr;
+  sock *send;
+};
+
+struct rip_packet_heading {
+  u8 command;
+  u8 version;
+#define RIP_V1 1
+#define RIP_V2 2
+  u16 unused;
+};
+
+struct rip_block {
+  u16 family;	/* 0xffff on first message means this is authentication */
+  u16 tag;
+  u32 network;
+  u32 netmask;
+  u32 nexthop;
+  u32 metric;
+};
+
+struct rip_entry {
+  node n;
+  ip_addr whotoldme;
+
+  ip_addr network;
+  ip_addr netmask;
+  ip_addr nexthop;
+
+  int metric;
+  u16 tag;
+
+  bird_clock_t updated, changed;
+};
+
+struct rip_packet {
+  struct rip_packet_heading heading;
+  struct rip_block block[25];
+};
+
+struct rip_data {
+  struct proto inherited;
+  sock *listen;
+  timer *timer;
+  list connections;
+  list rtable;
+  int magic;
+};
+
+#define P ((struct rip_data *) p)
+#define E ((struct rip_entry *) e)
+
+#define RIP_MAGIC 81861253
+#define CHK_MAGIC do { if (P->magic != RIP_MAGIC) die( "Not enough magic\n" ); } while (0)